Abstract: The present invention provides methods for predicting or modeling a chemotherapy outcome for a given patient, to assist physicians in the selection of chemotherapeutic agents for individualized cancer treatment.

Abstract: The present invention provides methods for preparing drug response and/or resistance profiles for breast tumor specimens, or cells derived therefrom. The drug response and/or resistance profiles are useful for determining effective chemotherapeutic agents for treatment of the tumor or cell to thereby individualize patient therapy. In other aspects, the invention provides a method for identifying a pathway or gene expression signature indicative of a breast cancer cell's sensitivity to a chemotherapeutic agent, which is useful for identifying a population response rate, or patient sub-population likely to respond to the drug candidate.

Abstract: The present invention provides methods for preparing a gene expression profile of a breast cancer cell, tumor, or cell line, where the gene expression profile may be evaluated for one or more gene expression signatures indicative of multidrug resistance. The signature may be indicative of resistance to one or more chemotherapeutic agents selected from a Taxol (e.g., Docetaxel or Paclitaxel), an antibiotic (e.g., Doxorubicin or Epirubicin), an antimetabolite (e.g., Fluorouracil and/or Gemcitabine), and an alkylating agent (e.g., Cyclophosphamide). Generally, the gene expression profile contains the level of expression for a plurality of genes listed in FIGS. 3, 4, and/or 5. Gene expression profiles for evaluating multidrug resistance for ER positive and ER negative breast cancers are also provided.